Tethered Hydroplane Classes and British Records
NAVIGA International Classes. Current Records
|A1 up to 3.5cc 1.2kg Ex Dia 7.0mm||Rashid Chabibulin||06/08/2016||213.777kph (132.75mph)|
|AE Electric 1.2kg 42v Max||Oleksi Smolnikov||30/07/2017||233.463kph (144.98mph)|
|A2 up to 7.5cc 2.0kg Ex Dia 8.0mm||Vladislav Subbotin||26/08/1999||218.871kph (135.92mph)|
|A3 up to 10cc 2.5kg Ex Dia 10mm||Vladislav Subbotin||05/07/2004||232.259kph (144.23mph)|
|B1 2.5cc airscrew 0.75kg Ex Dia 5.0mm||Babken Shahazizian||30/07/2017||284.360kph (176.58mph)|
|B1E airscrew 0.75kg 42v Max||Farid Ishmetov||30/07/2017||273.556kph (169.87mph)|
MPBA 'International' Classes.Current Records
|A1||Pete Dirs||13/08/17||122.64 mph|
|AE||No record established|
|A2||Roger James||3/08/03||129.30 mph (Set with 6.5cc motor)|
|A3||Norman Lara||06/07/14||141.70 mph|
|B1||Jim Free||10/04/00||154.91 mph|
|B1E||No record established|
|Pete Dirs||Roger James||Norman Lara||Jim Free|
MPBA British Classes. Current Records
|Sport 40 E||Martin Broad||20/07/14||111.29 mph|
|Sport 40 IC||Angela Gullick||27/08/17||106.77 mph|
|B1 Sport||Jim Free||28/05/17||128.48 mph|
|B||Ron Hankins||19/06/16||124.76 mph|
|B/S 9lb||Stan Poyser (deceased)||02/08/98||96.67 mph|
|A||John Hyder||08/10/00||130.05 mph|
|A/S||Paul Windross||07/07/13||129.33 mph|
|B/R||Ron Hankins||11/09/16||137.88 mph|
|Vintage||Not applicable to this class. Lambert Trophy awarded for the fastest speed recorded each season|
|Ron Hankins||The late Stan Poyser||Angela Gullick|
|Paul Windross||Left: Martin Broad|
|A1 1.2kg||Waterscrew up to 3.5cc. Straight fuel. *All waterscrew classes must run with silencers*|
|A1E 1.2kg||Electric Max 42V|
|A2 2.0kg||3.5cc to 7.5cc Straight fuel|
|A3 2.5kg||7.5cc to 10cc Straight fuel|
|B1 0.75kg||2.5cc airscrew Straight fuel 5.0mm max exhaust dia|
|B1E 0.75kg||Electric airscrew, max 42v|
|Sport 40 4.0lbs||6.5cc side exhaust 2-stroke. 10cc 4-stroke . Commercial components Free fuel|
|Sport E 4.0lbs||6 cell 22.5v electric|
|B1 Sport 2.0lbs||£90 limit on motor, 5mm exhaust outlet, commercial propellers. Free fuel|
|B Class 8.0lbs||Up to 15cc homebuilt engines. Free fuel|
|B/S Class 9.0lbs||Steam powered, all up weight not to exceed 9lbs.|
|A Class 16.0lbs||Up to 30cc homebuilt engines. Free fuel|
|A/S Class 16.0lbs||Steam powered, all up weight not to exceed 16lbs.|
|B/R 6.0lbs||Commercial engines up to 15cc. Free fuel|
|Vintage||Waterscrew or Airscrew, pre 1963 boat or design with engine of contemporary date.|
B1 & B1 Sport. WHAT'S THE DIFFERENCE?
On first glance both of these airscrew hydroplanes are very similar. They are both powered by 2.5cc engines, are both about the same weight, the engine mounting being the most obvious difference. One being a side mounted set up, the other being inverted. They are in fact quite different when it comes to power, speed and most definitely cost.
Let us first take the boat at the bottom. This is the open class B1 hydro, built from quite high tech materials such as carbon fibre, Kevlar, alloys of one sort or another, with some lime and balsa. The whole thing is covered in epoxy. The power for this boat comes from a Russian made Cyclon TOP 2.5cc engine costing some £500. Competition fuel is 80%-20% methanol, castor oil mix. For the top boats in the class, speeds of 160-170 mph can be expected.
The top boat is quite a different kettle of fish. This is the B1 Sport where certain elements are "RESTRICTED".
What are these restrictions?
The first thing to remember is that this class is mainly aimed at the beginner in the sport. Materials used in the hull construction are now free, but all parts must easily obtained commercially via local model shop etc. The engine is the area where costs and performance are controlled and has a maximum price of £90, which is reviewed annually and must not be modified. However there is now no restriction on the fuel used . The record for the B1R class, which this replaces is a tad over 120 mph. So there you have it, two boats that on the surface look very much the same, but that are quite different.
Thanks to Jim Free for this description of the two airscrew classes
|Commercial engine 'Sport 40'||15cc from castings 'B'||30cc from bar stock 'A'||Poppet valve flash steamer 'A/S'|
Records are correct at 01/01/18. Thanks to Norman Lara. Photos Jim Free, OTW, Sonia and Tony Collins.